In the article, the authors present the results of studies related to the effect of partial failures (PF) on the reliability characteristics of the system, determined through the probability of continuous operation over the interregional period under the conditions of continued operation after PF. The computational model is based on the assumption that the process of continuing to function after a spacecraft can be considered as redundancy by substitution, when the reserve appears capable of performing post-failure functions, but with some change in the reliability characteristics. The entire work interval is divided into separate sections inside, which the technical system operates with new reliability characteristics, with the sequential occurrence of several PF. A model with an exponential law of distribution of probabilities of partial failures is considered. It is believed that testing the device of the entire interregional period without a complete failure can be characterized as the product of the probabilities of the absence of a complete failure on the considered time interval, the absence of the occurrence of destructive external influences exceeding the critical values, the error-free processing of the program by the expert system and the absence of errors in the operator's actions. The results of the illustrative calculation are presented and conclusions are made.

Keywords: partial failure, redundancy, indicators of reliability of working out in the interregional period, calculated ratios for assessing reliability in case of partial failure

The article describes the correlation between the signal edge amount of sounding pulse and small irregularities detection in environments with dispersion. The analysis of experimental data on effective bandwidth of decameter waves spreading on the route Moscow-Ekaterinburg and results of wideband ground-penetrating radar sounding in natural environments with high dispersion gives the opportunity to experiment on surface, vertical and backward-inclined sounding. It is reported that the use of wideband electromagnetic pulses is perspective trend of progress in sounding of natural environments.

Keywords: electromagnetic sounding, decameter waves, electromagnetic pulses, small irregularities, permittivity, ground-penetrating radar sounding, dispersion, natural environment, vertical sounding, spectral form, ionosphere

This paper contains an analysis of the modeling results of the electrophysical parameters of light-emitting GaInAsSb / GaSb solid solutions. The model takes into account three types of current - drift, thermionic emission and tunneling through potential barriers. In the work, graphs of radiation power versus current strength and current-voltage characteristic (IVC) of the LED device are plotted. Modeling indicators based on the features of the band structure of semiconductor systems have been built. Experimental results were discussed, which showed satisfactory agreement with the data obtained on the basis of calculations.

Keywords: solid solutions, Sim Windows 1,5, radiating structures, currents limited by space charge, electrophysical parameters

The relevance of the study of two-dimensional periodic graphene gratings in the terahertz range is described. The structure under study and the results of calculation of scattering and reflection diagrams of multilayer structures are presented.The relevance of the study of two-dimensional periodic graphene gratings in the terahertz range is described. The structure under study and the results of calculation of scattering and reflection diagrams of multilayer structures are presented.

Keywords: Golovacheva E.V., Ivanova I.N., Gribnikova E.I., Makhno V.V.

The proposed combined device for assessing the quality of motor oils. To increase the informativeness of the output data, the device uses an optical method for analyzing the contamination of motor oils and a method for assessing contamination from changes in the dielectric constant.

Keywords: lubricant, optoelectronic device, internal combustion engine, engine oil, pollution analysis method, optical control method, dielectric constant

The rotor shaft of the turbocharger is the part that determines the life of the bearing unit. Various methods of restoring the working capacity of the rotor shaft have been developed. The most common of them-treatment for repair size and applying a layer of metal coating in various ways. After that, the rotor shaft is subjected to dynamic balancing, in order to ensure the minimum allowable imbalance. Stands on the basis of microprocessor-based two-plane balancing device PB-02M are widely used in the repair industry at the present time. The article deals with the process of dynamic balancing of restored rotors. The features of this process in relation to the conditions of repair production are noted. This is a large range of repaired units and the instability of the size of the bearing surfaces after the restoration. It is necessary to adjust the balancing device for each rotor. The case in which the initial rotor imbalance is much higher than the permissible one is also considered. It is necessary to carry out balancing in several stages. Pre-balancing - this is the first stage. Then the final balancing is made to the permissible imbalance value. The article presents a general algorithm for balancing rotors on balancing stands equipped with a measuring system based on the device PB-02M. The presented approach in the application of the measurement system allows to balance the parts with the required accuracy. This will ensure a high post-repair life of the repaired unit and the whole unit.

Keywords: turbocharger, rotor, repair, restoration, machine, balancing, adjustment, unbalance, device, algorithm

The article is devoted to the actual problem of increasing the complexity of user passwords in systems with remote access to increase their information security. It proposes a method based on the integrated application of the input characters of the password and the time intervals between them. In the article, using the inhibitor time network Petri, a model of a dynamic password setting process was constructed, on its basis the process of forming a reference image and user authentication is described. The above calculations of increasing the complexity of the password prove the effectiveness of the proposed approach.

Keywords: authentication, password, dynamic process, Petri net, complexity, password retrieval

This article discusses the economic approach to the choice of the mode of continuation of the system in the face of partial failure. It discusses strategies related to the continuation of work in conditions of partial failure or cessation of operation until the completion of the operational restoration process. The characteristics of each of the strategies are presented in a comparative aspect for the continuation of the operation of the object in the post-failure period or the delay in operation for the duration of the restoration. The dependence of the time recovery parameters and the times defining the moment of identifying a partial failure in the coordinates of the time axis from the beginning of the working cycle to the next scheduled maintenance has been revealed. The resulting mathematical expressions allow, under certain conditions, to justify the choice of one of the two strategies considered. For more complex cases, it is proposed to use expert approaches to take into account additional characteristics of the process, such interregional period, performance and acceptable risks associated with working in conditions of partial failure. The article provides graphs illustrating the change in reliability characteristics in two ways of developments of events related to the adoption of a decision to continue work.

Keywords: partial failure, the coefficient of gain in terms of work, the probability of uptime, recovery time, time in the post failure period

The process of analysis and modeling is proposed to be carried out in three stages: determinism, stochasticity and adaptability. The essence of these stages is revealed. The authors highlight the problem of predicting changes in partial failure, affecting the state of the technical system. The main distinctive features of such a refusal from the full (partial loss of working capacity, reducing the number of functions performed, and others) are shown. A diagram of the development of possible degradation processes in a technical facility as a result of partial failure is presented. Transitions to the states of several consecutive partial failures or transitions to a complete failure after one or several partial ones are possible. With getting into a state of complete failure, the object is fully restored. Developed proposals for the sequence of operations for the identification of failures at the level of the generalized algorithm. An illustrative example considers a fragment of the transition of a partial failure to another partial failure, which develops into a complete failure with the impossibility of further functioning of the electric machine for its intended purpose. The conclusion is made about the need to use expert systems and assessments for making decisions about functioning in conditions of partial failure.

Keywords: partial failure, critical failure, degradation change failure, diagnostic task, electric machine

The problem of recognition of defects in the surface layer of polished raceways of bearing rings according to the fractal dimension of the signals of the eddy current sensor is considered

Keywords: fractal dimension, defect recognition, recognition algorithm

Aspects of determination of pressure losses in local resistances at hydraulic calculation of underground polyethylene gas pipelines are considered. Calculation of coefficient of local resistance of saddle branch of firm FRIALEN (Germany) is resulted. The analysis of the dependence of the local resistance coefficient on the geometric parameters of the main gas pipeline and the gas pipeline-input is given.

Keywords: gas pipeline, hydraulic calculation, pressure loss, coefficient of local resistance, gas consumption, geometrical parameters

The main disadvantages of the methods of diagnosing the cylinder-piston group used at present are indicated in the article. Mathematical dependencies and the technique of technical diagnosing of a cylinder-piston group of diesel engines with a cold starting cranking of a cranked shaft developed on their basis are offered.

Keywords: engine, cylinder-piston group, compression,diagnosis, cold idle cranking of the crankshaft

The relevance of the research efficiency of known mechanization variants of concrete works during the construction of multi-storey buildings with monolithic frame is justified in the article. The data about the areas of rational choice specified and fulfilled by the authors, advantages and disadvantages of such methods are generalized and systematized. The features of the peculiarities of three of them, the most significant for the research are considered in detail. At the same time the results of the evaluation of their effectiveness in terms of unit labor and financial costs in the construction of frames of single-section tower-type buildings are presented, making it easier to optimize the choice of appropriate solutions in the organizational and technological design.

Keywords: monolithic frame building, concrete works, mechanization variants, efficiency, unit labor costs, unit financial costs

The legal status of water bodies implies special measures aimed at preserving and preventing negative processes within the boundaries of a water body. A zone with a special mode of use is the territory, within the boundaries of which the mode of using the object for the purpose of protection and (or) to protect the environment is established. In modern geodesy, special satellites are used that are part of the global positioning system. The object is tied to the existing geodetic network, the identification marks are laid in a minimal amount, then aerial photography is performed and the photoplans are “stitched”. The emergence of electronic and unmanned measuring instruments during a complex of geodetic works greatly facilitated the work of geodetic engineers, allowing them to increase the productivity and accuracy of work performed when using such instruments.

Keywords: water protection zone, zones with a special mode of use, water bodies, unmanned aerial vehicles, coastline, coastal protective strip, aerial photography, GNSS receivers, surveying equipment, orthophotomap

This article describes problems of ensuring the reliability of gas pipelines, one of which is connected with the construction of the North Seas on the shelf in the zone of permafrost soils, the other with the construction of long-distance gas pipelines in difficult hydrological conditions. Were analyzed the existing technical solutions in the light of the above construction conditions. Were revealed the advantages and disadvantages of the considered technologies of construction and transportation of gas are. The research identifies the main factors affecting the reliability and efficiency of design solutions for the construction of gas pipelines in areas with difficult hydrometeorological conditions.

Keywords: reliability of gas pipelines, analysis of technical solutions, complex hydrometeorological conditions, gas transportation